Airplanes are vehicles capable of flight by way of wings that interact with pressure and airflow to generate lift. A wing has an air foil cross sectional shape that generates lift by creating a pressure differential where there is a high pressure below the wing and low pressure above the wing. In this way the pressure differential supports the weight of the aeroplane in flight.
Airplanes have been utilised extensively since the 1950's to transport people and goods about the troposphere. The troposphere ranges from about 0 km to 12 kms from the earth's surface. An airplane typically includes, among other components, a body or fuselage, one or more wings intersecting the fuselage, landing gear to assist take-off and landing, an engine to provide thrust and a series of stabilisers to assist with control. Stabilizers are typically surfaces extending from the plane (such as around the tail) that have panels that can be moved by the pilot or onboard computer to assist in stabilizing the plane during flight. Most commercial airliners have both vertical stabilizers (incorporating a rudder) and horizontal stabilizers (incorporating an elevator) at the tail of the plane. The stabilizers are moved by the pilot manually or automatically by way of an onboard control computer connected by cables to a series of motors or actuators that mechanically move the panels (stabilizers) as needed.
Further developments have seen airplanes and space planes fly nonstop around the world and reach the stratosphere (about 12 km to 50 km), mesosphere (50 to 80 km), thermosphere (80 to 700 km) and exosphere (700 km to 10,000 km). With the ongoing use of airplanes for transport and the future of space tourism, there is a need for commercial aerospace planes (a combination of an airplane and space plane). There is also a need for an “aerospace plane system” for military applications. Such an aerospace plane should be fuel efficient and capable of a global transit (21600 nautical miles—nm) and capable of semi-planetary navigation (that is, reaches the thermosphere, the lower part known as the ionosphere) with a payload that is competitive in the commercial aviation arena.
The aerospace plane system should be sufficiently efficient to reduce the overall fuel flow to an average of 5.34 t/hr at Boeing 777 payloads with beyond Boeing 777 ranges to approximately 11000 nm and arrive at the destination with suitable fuel reserves, for example.
Airplane efficiency is effected by the AC (aerodynamic centre) and CG (centre of gravity) position relationship. Therefore, consideration must be given to the vertical and horizontal stabilizers which are currently utilized in most commercial planes. Currently a net downward balancing force is created by a horizontal stabilizer resulting in ‘induced and trim’ drag reducing aerodynamic efficiencies. This significantly reduces aircraft range and payload capacity for a given fuel load.
The McDonnell MD-11 for example, was designed as a relaxed stability airplane and some jet upsets (unusual flight attitudes) resulted. Attitude is the planes angle, up or down with respect to the earth. Jet upsets are extremely undesirable and it is therefore important to both design flight control software and flight control surfaces with sufficient power, CM (Coefficient Moment) and size to overcome these issues.
Present commercial airliners fly in the 33 000′ to 39 000′ range resulting in higher indicated airspeeds, than aircraft flying at higher levels beyond 60 000′, which results in much higher fuel usage rates. Therefore at lower altitudes more fuel is required to fly a specific distance, this increases costs, limits ranges and reduces payload/revenue. To achieve lower fuel flows a diversion from traditional commercial airplane shapes is desirable so that a majority of the flight is conducted with the CG (centre of gravity) aft (rear) of AC (Aerodynamic centre) and therefore CG management is required to achieve this.
There is also a need to design an aerospace plane capable of flying extreme ranges and carry more payload per unit of fuel used than existing commercial airplanes.
Also, current commercial airplanes require at least two crew members to operate a plane where up to six pilots (as relief crew) may be required to fly extreme ranges to comply with Federal Aviation Regulations (FARs) or the equivalent. This increases airplane operating costs by requiring more crew to operate a fleet of airplanes. Accordingly, there is a need to design an aerospace plane to be operated by one crew member only thereby reducing labor costs therefore requiring fewer relief crews for extreme range operations.
It is an object of the present invention to substantially overcome or at least ameliorate one or more of the disadvantages of the prior art, or to at least provide a useful alternative.